The use of the additive TBZC as a source of zinc in animal nutrition would not lead to different zinc concentrations in food of animal origin compared with another authorised inorganic zinc source, and consequently it is considered safe for consumers. The additive TBZC should be considered as a potential irritant to skin and eyes and a potential skin sensitiser. The risk of respiratory exposure is considered to be minimal. The use of zinc-containing feed additives does not pose a direct environmental concern for agricultural soils, but the available data were not sufficient to exclude any risk related to drainage and the run-off of zinc to surface water. The use of zinc-containing additives in aquaculture up to maximum authorised zinc level in feeds is not expected to pose an appreciable risk to the environment. The additive TBZC is an efficacious source of zinc in terms of meeting animal requirements.
Following a request from the European Commission, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety and efficacy of tetra-basic zinc (TBZC) chloride for all species. The additive TBZC consists of ≥ 84 % zinc chloride hydroxide monohydrate, ≤ 9 % zinc oxide and about 5 % starch.
Zinc is the second most abundant trace element, after iron, in most vertebrates. It is required for a variety of basic biological processes including metabolism of proteins, nucleic acids, carbohydrates and lipids, and it is also involved in more complex processes, such as the immune response, neurotransmission and cell signalling. It is an integral component of all proteins, in which it contributes to tertiary structure or catalytic activity.
The FEEDAP Panel concluded that the additive TBZC is a safe source of zinc for all animal species, considering the maximum contents for total zinc in feedstuffs set by the European Union.
The use of the additive TBZC as a zinc source in animal nutrition would not lead to different zinc concentrations in food of animal origin compared with another authorised inorganic zinc source. The FEEDAP Panel concluded that the additive TBZC is safe for consumers when used as a supplemental source of zinc in animal nutrition up to the maximum authorised levels of total zinc in feedingstuffs.
The FEEDAP Panel concluded that the additive TBZC should be considered as a potential irritant to skin and eyes and a potential skin sensitiser. The risk of respiratory exposure is considered to be minimal.
The use of zinc-containing feed additives does not pose a direct concern for the agricultural soil compartment. However, there is a potential environmental concern related to drainage and the run-off of zinc to surface water. Acid sandy soils are most vulnerable to these processes. In order to draw a final conclusion, some further refinement to the assessment of zinc-based feed additives in livestock needs to be considered, for which additional data would be required. The use of zinc-containing additives in aquaculture up to maximum authorised zinc level in feeds is not expected to pose an appreciable risk to the environment.
The additive TBZC is an efficacious source of zinc in terms of meeting animal requirements.
The FEEDAP Panel made some recommendations concerning the specifications of the additive.
